Zika and Ebola: A taste of things to come?

By Dr Seth Berkley-26 February 2016

Ebola. Zika. Both diseases that were unknown to many until recently. But there have been huge outbreaks of both - and each time scientists and global health experts were caught off guard.

In this week's Scrubbing Up, Dr Seth Berkley, CEO of the Gavi, the Vaccine Alliance suggests Ebola and Zika may be followed by other public health emergencies fuelled by other lesser-known diseases.

First it was Ebola and now Zika; two official World Health Organization (WHO) Public Health Emergencies of International Concern within as many years.

Both diseases have been known about for decades, and yet in both cases no vaccines or drugs were available when we most needed them. So what's going on?

Is this just a terrible coincidence, being caught off-guard like this twice in such quick succession, or is it part of a worrying trend and a taste of things to come?

At first glance it wouldn't appear that the two diseases have much in common. One is difficult to catch but a ferocious killer, while the other spreads with ease but is relatively harmless to the vast majority of people infected.

Yet, in both cases there is something novel, either in the way the virus has spread or in how it affected people which has made the outbreaks more of a threat.

In global health security terms that is a real concern, because such sudden changes of modus operandi can not only make public health threats even more difficult to predict or anticipate than normal, but also make all the difference between a localised outbreak and global pandemic.

Even more worrying is the fact that with changing trends in human and animal migration, increasing urbanisation, the density of mega cities, the rise in antimicrobial resistance and climate change, such threats could become increasingly more common.

In the case of Ebola, what changed was its ability to spread.

Historically Ebola's aggression has been its own worst enemy; the virus often immobilising and killing its hosts before they had the opportunity to infect others, limiting its spread mainly to contact with the deceased.
                                             Read More